Fibromyalgia is a disease with chief complaints of systemic diffuse pain and fatigue and with objective symptoms of characteristic tender points. It is said that psychosomatic disorder-like symptoms such as sleep disturbance, anxiety, depression and fretfulness and/or associated disorders such as frequent urination, irritable bowel syndrome, dysmenorrhea and sicca syndrome are often observed in fibromyalgia. It has been known that, as the symptoms of fibromyalgia progress, patients may feel severe pain even when they receive a slight stimulus, and that thus the daily life becomes difficult and the quality of life will be markedly reduced.
The current diagnosis of fibromyalgia in Japan has been performed based on the classification criteria of the American College of Rheumatology which was published in 1990 (Wolfe et al., Arthritis Rheum., 1990, Vol. 33, p. 160). Although the pathogenic mechanism of fibromyalgia has not yet been clarified, it is thought that its pathogenic mechanism would be different from that of nociceptive pain which is caused by damage to the living body or that of neuropathic pain which is caused or evoked by temporal damage or dysfunction in the nervous system, since it is not accompanied by inflammation nor nerve damage.
As therapeutic agents for fibromyalgia, pregabalin which is a calcium channel blocker, and duloxetine and milnacipran which are antidepressants having a serotonin noradrenaline reuptake inhibition (SNRI) action have been approved by the U.S. Food and Drug Administration, and some of nonsteroidal anti-inflammatory agents have been used as they are considered to be effective in treating fibromyalgia (Nickerson B, US Pharma., 2009, Vol. 34, p. 49).
However, at present, the analgesic effect of pregabalin and duloxetine which has been approved as a therapeutic agent for fibromyalgia may be poor in some patients, and there are large individual differences in the efficacy of the drugs among patients. In cases of ibuprofen and naproxen which are nonsteroidal anti-inflammatory agents, it has been reported that any statistically significant analgesic effect is not observed in treating fibromyalgia (Abeles et al., Am J. Med., 2008, Vol. 121, p. 555). Therefore, a new drug that has a strong analgesic effect on pains caused by various mechanisms and is effective in a wide range of fibromyalgia patients has been strongly demanded to be discovered.
On the other hand, in regard to a pyrazole derivative (WO 08/105,383) and a cyclohexane derivative of the following Formula which has a sulfonyl group on the aromatic ring linked to the pyrazole ring (WO 00/066562), therapeutic effects thereof on nociceptive pain and/or neuropathic pain are disclosed, but its application as a pharmaceutical for any specific disease such as fibromyalgia is neither disclosed nor even suggested:

Accordingly, it could be helpful to provide a therapeutic agent or prophylactic agent which has an analgesic effect on both nociceptive pain and neuropathic pain and is effective in treatment of fibromyalgia.